a. Field
The present disclosure relates generally to assessing a person's risk of developing cardiovascular disease. In particular, the present disclosure relates to a vascular age calculator based on flow-mediated dilation.
b. Background
Cardiovascular disease (CVD) is a leading cause of morbidity and mortality. Consequently, CVD risk assessment continues to be a key focus in primary medical care settings.
Multivariable risk prediction algorithms have been used to assess CVD risk and guide treatment of risk factors. For example, the Framingham Heart Study (FHS), based on a long-term study of a population of individuals, relates age, total and high-density lipoprotein cholesterol, systolic blood pressure, treatment for hypertension, smoking, and diabetes status to a quantitative risk of CVD, expressed as a percent chance of having a CVD event in ten years. General CVD risk point scores and vascular age data are described in D'Agostino et al., “General Cardiovascular Risk Profile for Use in Primary Care: The Framingham Heart Study,” Circulation 2008, 117:743-753.
More recent CVD risk assessment techniques have focused on the correlation between early stage CVD and the ability of arteries to dilate in response to increased blood flow. Brachial artery flow-mediated dilation (FMD) has been used by numerous investigators to evaluate cardiovascular health. One study, Inaba et al., “Prediction of future Cardiovascular Outcomes by Flow-Mediated Vasodilation of Brachial Artery: A Meta-Analysis,” Int J Cardiovasc Imaging 2010, 26:631-640, determined a pooled relative risk (0.87) of cardiovascular events per 1% increase in brachial artery FMD.
U.S. Pat. No. 8,057,400, which is commonly owned and incorporated herein by reference in its entirety, describes a medical diagnostic method, device, and system for non-invasively assessing the ability of arteries to respond to an increase in blood flow. Volume pulse wave amplitudes or other components are used to provide an indication of FMD, and, consequently, CVD risk.